convert : fix another python 3.8 issue (#2949)

diff --git a/convert.py b/convert.py
index 5cc3f6e66f6bbf893a33ef70b8ead7af6c518d98..6c89b5ecc7f450364a9c78ac52baac1c8c0526a9 100755 (executable)
--- a/convert.py
+++ b/convert.py
@@ -530,7 +530,7 @@ class LazyTensor:
             raise ValueError(f'Cannot validate conversion from {self.data_type} to {data_type}.')
 
 
-LazyModel = dict[str, LazyTensor]
+LazyModel: TypeAlias = 'dict[str, LazyTensor]'
 
 
 @dataclass